Smart gadgets are everywhere. The chances are you have them in your workplace, in your home, and perhaps on your wrist. According to an estimate from research firm Gartner, there will be over 11 billion Internet-connected devices (excluding smartphones and computers) in circulation worldwide this year, almost double the number just a couple of years ago.

Many billions more will come online soon. Their connectivity is what makes them so useful, but it's also a cybersecurity nightmare. Hackers have already shown they can compromise everything from connected cars to medical devices, and warnings are getting louder that security is being shortchanged in the stampede to bring products to market.

In a new book called Click Here to Kill Everybody, Bruce Schneier argues that governments must step in now to force companies developing connected gadgets to make security a priority rather than an afterthought. The author of an influential security newsletter and blog, Schneier is a fellow at the Berkman Klein Center for Internet and Society at Harvard University and a lecturer in public policy at the Harvard Kennedy School. Among other roles, he's also on the board of the Electronic Frontier Foundation and is chief technology officer of IBM Resilient, which helps companies prepare to deal with potential cyberthreats.

Schneier spoke with MIT Technology Review about the risks we're running in an ever more connected world and the policies he thinks are urgently needed to address them.

The title of your book seems deliberately alarmist. Is that just an attempt to juice sales?

It may sound like publishing clickbait, but I'm trying to make the point that the internet now affects the world in a direct physical manner, and that changes everything. It's no longer about risks to data, but about risks to life and property. And the title really points out that there's physical danger here, and that things are different than they were just five years ago.

How's this shift changing our notion of cybersecurity?

Our cars, our medical devices, our household appliances are all now computers with things attached to them. Your refrigerator is a computer that keeps things cold, and a microwave oven is a computer that makes things hot. And your car is a computer with four wheels and an engine. Computers are no longer just a screen we turn on and look at, and that's the big change. What was computer security, its own separate realm, is now everything security.